Key points
- The key to preventing Legionnaires' disease is to control Legionella growth and spread.
- Buildings and devices at increased risk for Legionella growth and spread should have a water management program based on industry standards.
- Owners of certain devices, like hot tubs, should take steps to reduce Legionella risk.
Overview
Bacteria called Legionella cause Legionnaires' disease. Legionella is found naturally in freshwater environments and can become a health concern in human-made building water systems.
Reducing risk
Outbreaks can be prevented
Use effective water management programs
Buildings and devices at increased risk for Legionella growth and spread should have a water management program.
CDC has developed a number of resources for building owners and managers on how to develop an effective water management program:
- Overview: Water management programs
- Toolkit: Developing a water management program to reduce Legionella growth and spread in buildings
- Training: Preventing Legionnaires' disease: A training on Legionella water management programs
- Worksheet: Identify buildings with increased Legionella risk
Operate and maintain devices safely
Owners of the following devices should follow the manufacturer's instructions regarding cleaning, disinfecting, and maintenance:
- Cooling towers
- Decorative fountains
- Hot tubs
- Centrally installed misters, atomizers, air washers, or humidifiers
CDC has developed a toolkit on how to control Legionella in common sources of exposure, including decorative fountains and hot tubs.
Hot tub resources
To help control Legionella, the levels of disinfectants and chemicals in hot tubs should be checked regularly. Learn how to test the water before you use a hot tub. Consider what questions to ask a hot tub operator to find out if it's been properly maintained.